Environment Southland is keeping a close eye on its drying-up water supply.
The Edendale aquifer has recorded its lowest level on record since monitoring began in 2001.
Environment Southland spokesman Graham Sevicke-Jones says it is concerning.
"We may go into next summer with lower than normal levels in the aquifer, which means that problems we've experienced this year - if the same sort of weather plays out - could be worse."
An investigation is underway to look into the matter.
Mr Sevicke-Jones says one option is to dig deeper, but it comes at a cost.
"That requires consenting of course… and secondly, [there are] legal requirements."
He's blamed the region's dry summer is a major factor.
"What they thought was a secure supply might not be quite the case. We'll certainly have to review how we approach our allocations to make sure it's still all sound."